The present invention relates generally to improvements in intelligent telecommunications networks. More particularly, the present invention relates to a system and method for detecting and processing armed triggers using a distributed intelligent network triggering architecture.
An intelligent network is a network architecture offering advanced services to telecommunication subscribers. Irrespective of the telecommunication network technology, intelligent networks enable network operators to provide a wide variety of telecommunications conveniences and services by allowing interaction with database systems and intelligent peripherals. The intelligent network is applicable to both fixed networks, where it is commonly referred to as an Advanced Intelligent Network (AIN), and to mobile networks, where it is referred to as a Wireless Intelligent Network (WIN). Outside North America, essentially the same technology is applied as European Telecommunications Standards Institute (ETSI) Core Intelligent Network Application Part (INAP) and Global System for Mobile Communication (GSM) Customized Applications for Mobile Network Enhanced Logic (CAMEL) for fixed and mobile networks, respectively. When a service subscriber/user requests an advanced service, thereby making an intelligent network call, the local exchange or serving mobile switching centre equipped with Service Switching Point (SSP) functionality processes the call, or it may transfer the call to an appropriately equipped exchange. For recognition and activation of an intelligent network service, the intelligent network architecture is characterized by the use of predefined triggers for the service, the triggers including the triggering criteria used for activation of the service. These triggers extend call processing through the execution of remote service logic stimulated in response to a predefined triggering stimulus (e.g., detection of certain dialled digits, specific call status events, etc.)
In the existing intelligent network architecture, detection of armed triggers, trigger condition checking and associated trigger processing all take place within the service switching point. After triggering on an incoming intelligent network call by checking and verifying that the trigger conditions have been met, the service switching point sends a message containing information on the initiating trigger and general call information to a service control point located in the same or a different location. During an intelligent network call, a number of such messages may be sent between the service switching point and the service control point. The service control point invokes appropriate service logic to analyze thie received message in order to identify the requested service. The service control point then issues one or more commands to the service switching point to initiate the appropriate actions to fulfil the requested service. The service control point may also provide charging information.
For a wireless subscriber, the location and subscriber data, including the trigger profile, (e.g., an ANSI-41 TriggerAddressList parameter), is stored in a home location register for the subscriber, and must be transferred to a visitor location register associated with a visited service switching point. Thus, the trigger profile must follow the subscriber during roaming, which requires the transfer of a complete list of triggers, each with its own service logic program address and possibly other criteria depending on the nature of the trigger. Thus, it is necessary that a complex WIN trigger profile be transferred along with the roaming subscriber for local processing in the visited service switching point in order to support the services subscribed to. This profile becomes more complex as more services and features are subscribed to. Even with only a few services, or with only a few instances of complex trigger criteria, a WIN trigger profile rapidly becomes unmanageable where the signalling infrastructure is limited to relatively short messages (e.g., 255 bytes in Signalling System No. 7 (SS7) Transaction Capabilities Application Part (TCAP), which is a nearly universal situation in existing networks).
Furthermore, WIN services, as well as ubiquitous offering of new AIN services across a wide area, are currently constrained by the requirement to use legacy service switching points having varying capabilities (e.g., for WIN services, the visited switch serving the roaming subscriber may support a more restricted set of triggers and processing than the home switch, and hence restricts the range of services that can be supported) and containing software which must be updated whenever new triggers are defined, or new criteria for an existing trigger are defined. This results in limitations on service offerings which must await the wide deployment of the required support or software updates to the service switching points before the services requiring these triggers can be offered. This problem is especially constraining in mobile networks which must support roaming subscribers potentially from anywhere on the globe.
Finally, consistent service inter-working for roaming subscribers requires that the same set of triggering and trigger criteria processing capabilities and processing be duplicated on multiple service switching points, thus escalating service deployment cost and complexity.
It is, therefore, desirable to provide a method and system which simplifies the profile required to be distributed to visited service switching points for roaming subscribers.
It is an object of the present invention to obviate or mitigate at least one disadvantage of previous systems and methods for detecting and processing armed triggers in intelligent networks.
Generally, the present invention provides a method and system for detecting and processing armed triggers associated with specific call functions in an intelligent network, using a distributed intelligent network triggering architecture. The complex trigger profile is removed from the service switching point to a trigger processing server, so that a much simplified and reduced profile can be sent to the service switching points with a roaming subscriber, which overcomes the problem of lack of support for long messages within the signalling infrastructure. The reduced processing at the service switching point means that the detection points for armed triggers residing therein need only have a minimal triggering capability and a generic trigger for each detection point, and therefore do not need to be upgraded as new triggers are defined or as new criteria are defined for existing triggers. Such upgrades need only be dealt with in the trigger processing server and since the trigger processing server is normally part of the subscriber""s home network, or strategically located and shared amongst service providers through appropriate Service Level Agreements (SLAs), it can be upgraded as required to provide the subscriber with much greater consistency of services and features when roaming to other networks. This addresses the issue resulting from differences in SSP triggering capabilities implementation in a multi-vendor environment, and the related issue of differences in deployment of SSP software releases in a multi-operator environment, which is often the case for roaming subscribers.
In a first aspect, the present invention provides a trigger processing server for processing an armed trigger associated with an intelligent network call function. The trigger processing server consists of a trigger profile store, a trigger processor, and a call instruction aggregator. The trigger processor receives indication of armed triggers from remote detection points (i.e., SSPs), and then processes the armed triggers stored in the trigger profile store. The trigger processor then seeks call handling instructions from one or more remote service logic programs, as determined from the armed triggers, which are conventionally located at one or more service control points in the intelligent network, in respect of the authenticated triggers. The call instruction aggregator aggregates the call handling instructions received from the service logic programs, and, when all call handling instructions for armed triggers for a particular call have been received, instructs the service switching point to process the call according to the aggregated call handling instructions.
In a further aspect, there is provided an intelligent network switching system that includes the above trigger processing server, detection point(s), and service control point(s). The detection points can be located at service switching points, or at a terminal if the terminal has sufficient processing capabilities. If the intelligent network is a WIN, the service switching point is a mobile switching centre.
In yet another aspect, the present invention provides an intelligent network that includes the above intelligent network switching system, and an appropriate terminal capable of requesting an intelligent network call function and thereby arming a trigger. The intelligent network can be a wireless network, a fixed network, a circuit switched network, a packet-based network, or any combination thereof.
The present invention also includes a method for processing intelligent network call function triggers. The method commences by receiving an armed trigger at the trigger processing server, usually after its detection at a detection point remote from the trigger processing server. The armed trigger is then processed by comparison to a corresponding trigger profile stored at the trigger processing server. A call handling query in respect of the authenticated trigger is then transmitted to a service logic program at a service control point, and call handling instructions are received in response to the call handling query. Finally, when all call handling instructions have been received, they are transmitted to a service switching point for processing the call. The call handling instructions can be stored and aggregated until the trigger processing for the current detection point is completed.